1. Field of the Invention
The present invention relates to a piezoelectric element utilizing a longitudinal oscillation mode for use in an AM filter or other electronic components.
2. Description of the Related Art
In a known conventional piezoelectric element utilizing a longitudinal oscillation mode, a first main surface of a piezoelectric substrate is provided with input and output electrodes that are formed by dividing electrode material via a longitudinally extending linear groove, and a second main surface of the piezoelectric substrate is provided with a common electrode, wherein a part of each of the input and output electrodes is provided with a separate, independent support section which is formed of an isotropic elastic conductive material and which constitutes an electrical contact section for achieving electrical contact with an external conductor as described in Japanese Patent Unexamined Publication No. 2-224515. The above-mentioned support sections are arranged on either side of the groove and at a common position with respect to the longitudinal dimension of the input and output electrodes.
In the above-described piezoelectric element, the distance between the support members, which are spaced apart from each other, is small. Thus, when the piezoelectric element as described above is connected to external conductors, such as terminals of a case for an electronic component, with the input and output electrodes facing downwards, it is necessary for the external conductors to be located in close proximity to each other. Thus, if there is a small positional deviation of the piezoelectric element, a short circuit may be developed between the input and output electrodes.
In the above-described piezoelectric element, the elastic support sections thereof are connected to terminals of a case by bringing them into elastically biased contact with the terminals. In effecting this connection, the support sections may be connected and fixed to pattern electrodes of a mounting substrate or the like by using a conductive adhesive or the like. In this case, due to the small distance between the support sections of the input and output electrodes, a short circuit may be developed between the input and output electrodes if the conductive adhesive is spread to only a small amount, resulting in a deterioration in reliability of the electrical connection.